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Detection of coherent reflections with GPS bipath interferometry

Achim Helm·Georg Beyerle·Markus Nitschke
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Abstract

Results from a GPS reflectometry experiment with a 12 channel ground-based GPS receiver above two lakes in the Bavarian Alps are presented. The receiver measures in open-loop mode the coarse/aquisition code correlation function of the direct and the reflected signal of one GPS satellite simultaneously. The interference between the coherently reflected signal and a model signal, which is phase-locked to the direct signal, causes variations in the amplitude of the in-phase and quad-phase components of the correlation sums. From these amplitude variations the relative altimetric height is determined within a precision of 2 cm.

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Achim Helm, Georg Beyerle, Markus Nitschke. 2004-07-16. Detection of coherent reflections with GPS bipath interferometry. https://arxiv.org/abs/physics/0407091

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